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Finding the Fourth Proportional to 784, 1,078.08 and 680.32

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Solution

The fourth proportional to 784, 1,078.08 and 680.32 is: 935.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    784 : 1,078.08 = 680.32 : x
  2. Step 2: Convert to fraction form
    784/1,078.08 = 680.32/x
  3. Step 3: Cross multiply
    784x = 1,078.08 × 680.32
  4. Step 4: Simplify right side
    784x = 733,439.39
  5. Step 5: Solve for x
    x = 733,439.39/784
  6. Step 6: Final answer
    x = 935.51

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.